PathoPhysiology Chapter 23

CHAPTER 23
RESTRICTIVE PULMONARY
DISORDERS

DISORDERS
Result from Decreased Lung Expansion
• Alterations in lung parenchyma, pleura, chest
wall, or neuromuscular function
• Represent acute or chronic patterns of lung
dysfunctions (not a single disease)
• Classifications
• Pulmonary, extrapulmonary

DISORDERS (CONT.)
Characteristics
• Decrease in vital capacity (VC), lung
capacity (TLC), functional residual capacity
(FRC), residual volume (RV)
• The greater the decrease in lung volume,
greater the severity of disease
• ABG
• Decreased PaO2
• Normal or decreased PaCO2

LUNG PARENCHYMA DISORDERS
Fibrotic Interstitial Lung Disease
• Diffuse interstitial lung disease
• Diffuse interstitial pulmonary fibrosis
• Etiology
• Characterized by thickening of alveolar interstitium
• 5:100,000

(CONT.)
Diffuse Interstitial Lung Disease
• Pathogenesis
• Immune reaction
• Begins with injury to alveolar epithelial or
capillary endothelial cells
• Interstitial and alveolar wall thickening
• Increased collagen bundles in interstitium

(CONT.)
• Pathogenesis
• Immune reaction
• Lung tissue becomes infiltrated
• Persistent alveolitis leads to obliteration of
alveolar capillaries, reorganization of lung
parenchyma, irreversible fibrosis
• Lead to large air-filled sacs (cysts) with dilated
terminal and respiratory bronchioles

(CONT.)

(CONT.)
• Pathogenesis
• Inflammation
• Occurs early, reversible
• Triggering event leads to inflammatory response and
increased inflammatory cells
• Injury leads to increased membrane permeability and
movement of fluid/debris into alveoli

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Fibrosis
• Fibroblastic proliferation and deposition of large
amount of collagen
• Caused by increased mesenchymal cells and
fibroblasts in interstitium
• Alveolar walls become thickened with increased
amounts of fibrous tissue

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Destruction
• End-stage disease
• Loss of alveolar walls

LUNG PARENCHYMA
DISORDERS (CONT.)
• Clinical manifestations
• Progressive dyspnea with exercise with desaturation
• Rapid-shallow breathing
• Irritating, nonproductive cough
• Clubbing of nail beds (40%-80%)

LUNG PARENCHYMA
DISORDERS (CONT.)
• Bibasilar end-expiratory crackles (Velcro rales)
• Cyanosis (late finding)
• Anorexia, weight loss
• Inability to increase cardiac output with exercise

LUNG PARENCHYMA
DISORDERS (CONT.)

LUNG PARENCHYMA
DISORDERS (CONT.)
• Diagnosis
• Chest x-ray
• PFT (decreased VC, TLC, diffusing capacity)
• Open lung biopsy
• Transbronchial biopsy
• Gallium-67 scan
• Bronchoalveolar lavage

LUNG PARENCHYMA
DISORDERS (CONT.)
• Treatment
• Smoking cessation
• Avoid environmental exposure to cause
• Anti-inflammatory agents
• Immunosuppressive agents
• Lung transplant

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Etiology
• Chronic common in 3rd-4th decade of life
• North American blacks (35.5/100,000)
• Northern European whites (10.9:100,000)
• Acute or chronic systemic disease of unknown
cause
• Immunologic
• Activation of alveolar macrophage to unknown
trigger

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Pathogenesis
• Development of multiple, uniform, noncaseating
epithelioid granulomas
• Affects multiple organs
• Lymph nodes, lung tissue (most common)
• Skin, eyes, spleen, liver, kidney, bone marrow
• Fibrotic and surrounded by large histiocytes
• May occur in bronchial airways
• Abnormal T-cell function

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Malaise, fatigue
• Weight loss
• Fever
• Dyspnea of insidious onset
• Dry, nonproductive cough
• Erythema nodosum
• Macules, papules, hyperpigmentation, and
subcutaneous nodules
• Hepatosplenomegaly, lymphadenopathy

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Diagnosis
• Leukopenia, anemia
• Increased eosinophil count, elevated sedimentation
rate
• Increased Ca++
levels (5%)
• Elevated liver enzymes
• Anergy (70%)
• Elevated angiotensin-converting enzyme in active
disease (40%-80%)

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Diagnosis
• Gallium-67 scan
• Localize areas of granulomatous infiltrates
• Pleural effusion noted in 10% of cases
• PFTs
• Normal or show evidence of restrictive disease and/or
obstructive disease

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Diagnosis
• Bronchoalveolar lavage
• Monitors cell content
• Fluid has increased lymphocytes and high CD4/CD8
cell ratio
• Transbronchial lung biopsy
• Noncaseating granulomas (definitive diagnosis)
• Chest x-ray
• Differentiates stages

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Stages
• Stage 0
• Normal
• Stage 1
• Good prognosis
• Hilar adenopathy alone
• Stage 2
• Hilar adenopathy and bilateral pulmonary infiltrates

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Stages
• Stage 3
• Pulmonary infiltrates without adenopathy
• Stage 4
• Advanced fibrosis with evidence of honeycombing,
hilar retraction, bullae, cysts, and emphysema

LUNG PARENCHYMA
DISORDERS (CONT.)
Sarcoidosis
• Treatment
• Corticosteroids
• Immunosuppressive agents

LUNG PARENCHYMA
DISORDERS (CONT.)
Hypersensitivity Pneumonitis
• Etiology
• Known as extrinsic allergic alveolitis
• Restrictive and occupational disease
• Predominant in nonsmokers (80%-95%)

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Genetic predisposition
• Agent suggested by patient history
• Agent confirmed by precipitating antibodies in
serum
• Antigen combines with serum antibody in alveolar
walls; leads to type III hypersensitivity reaction

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Antigen-antibody complexes then elicit
granulomatous inflammation leading to lung tissue
injury
• Must have delayed hypersensitivity (type IV)
reaction to antigen to develop pneumonitis

LUNG PARENCHYMA
DISORDERS (CONT.)
• Acute
• Symptoms start 4-6 hr after exposure and resolve in 18-
24 hr
• General symptoms
• Chills, sweating, shivering
• Myalgias
• Nausea
• Malaise, lethargy
• Headache

LUNG PARENCHYMA
DISORDERS (CONT.)
• Acute
• Respiratory symptoms
• Dyspnea at rest
• Dry cough
• Tachypnea
• Chest discomfort
• Physical findings
• Cyanosis (late)
• Crackles in lung bases

LUNG PARENCHYMA
DISORDERS (CONT.)
• Intermediate
• Acute febrile episodes
• Progressive pulmonary fibrosis with cough
• Dyspnea, fatigue
• Cor pulmonale (right-sided heart failure related to lung
disorders)
• Chronic
• Progressive, diffuse pulmonary fibrosis in upper lobes
(hallmark of disease)

LUNG PARENCHYMA
DISORDERS (CONT.)
• Diagnosis
• Chest x-ray
• Acute/subacute
• Transient, bilateral pulmonary infiltrates
• Increased bronchial markings with alveolar nodular
infiltrates
• Chronic
• Diffuse reticulonodular infiltrates
• Fibrosis

LUNG PARENCHYMA
DISORDERS (CONT.)
• Diagnosis
• Skin testing with causative antigen
• Red, indurated hemorrhagic reaction 4-12 hr after
injection
• Laboratory
• Increased WBCs
• Decreased PaO2
• PFTs
• Decreased lung volumes, diffusing capacity,
compliance

LUNG PARENCHYMA
DISORDERS (CONT.)
• Treatment
• Identify offending agent and prevent further
exposure
• Oral corticosteroids

LUNG PARENCHYMA
DISORDERS (CONT.)
Occupational Lung Diseases
• Etiology
• Result from inhalation of toxic gases or foreign
particles
• Atmospheric pollutants have large effect on
occupational respiratory diseases

LUNG PARENCHYMA
DISORDERS (CONT.)
Occupational Lung Diseases
• Pneumoconiosis
• Caused by inhalation of inorganic dust particles
• Greater the exposure, the worse the consequences
• Anthracosis
• “Coal miner’s lung” or “black lung”
• Silicosis
• Silica inhalation
• Asbestosis
• Asbestos inhalation

LUNG PARENCHYMA
DISORDERS (CONT.)
Occupational Lung Disease
• Predisposing factors
• Preexisting lung disease
• Exposure to atmospheric pollutants
• Duration of dust exposure
• Amount of dust concentration
• Particle size of pollutant

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Pollutants interfere and paralyze cilia
• Interference with ciliary action
• Impaired clearance effect
• Inability to be removed

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Alveolar macrophages try to engulf and remove
• Migrate to small airways to use mucociliary escalator
• Engulf dust; exit through the lymph/blood system
• Migrate through bronchial walls, depositing dust
particles in extra-alveolar tissue
• Destroy the particle

LUNG PARENCHYMA
DISORDERS (CONT.)
• Pathogenesis
• Macrophages secrete lysozymes to control foreign
particle activity
• Enzymes damage alveolar walls causing deposition
of fibrous materials

LUNG PARENCHYMA
DISORDERS (CONT.)
• Symptoms depend on predisposing factor
• Pneumoconiosis produces no signs or symptoms in
early stage
• Usually symptom free up to 10-20 years with chronic
exposure

LUNG PARENCHYMA
DISORDERS (CONT.)
• Late clinical features
• Chronic hypoxemia
• Cor pulmonale
• Respiratory failure

LUNG PARENCHYMA
DISORDERS (CONT.)
• Diagnosis
• Chest x-ray
• No changes without symptoms
• With progression
• Micronodular mottling and haziness
• Nodules, fibroses, calcifications

LUNG PARENCHYMA
DISORDERS (CONT.)
• Diagnosis
• PFTs
• ABG
• Hypoxemia
• Hypercapnia

LUNG PARENCHYMA
DISORDERS (CONT.)
• Treatment
• Preventive measures are key to limiting onset and
severity
• Corticosteroids
• Bronchodilators
• O2 therapy

ATELECTATIC DISORDERS
Acute (Adult) Respiratory Distress
Syndrome (ARDS)
• Etiology
• Occurs in association with other pathophysiologic
processes
• 125,000-150,000 cases/year in United States
• Mortality rate 30%-60%

(CONT.)
ARDS
• Causes
• Severe trauma
• Sepsis (>40%)
• Aspiration of gastric acid (>30%)
• Fat emboli syndrome
• Shock

(CONT.)
ARDS
• Pathogenesis
• Widespread pulmonary inflammation leads to:
• Noncardiogenic pulmonary edema associated with
“leaky” pulmonary capillaries
• Atelectasis associated with lack of surfactant
• Decreases surface tension in small alveoli and prevents
them from collapsing
• Fibrosis (hyaline membranes)
• Associated with inflammatory deposition of proteins

(CONT.)
ARDS
• Pathogenesis
• Characteristic abnormalities
• Injury to alveoli from a wide variety of disorders
• Changes in alveolar diameter
• Injury to pulmonary circulation
• Disruptions in O2 transport and utilization

(CONT.)
ARDS
• Pathogenesis
• Common findings
• Severe hypoxemia caused by intrapulmonary shunting
of blood
• Perfusion of large numbers of alveoli that are poorly
(areas of low ventilation-perfusion) or not ventilated
(areas of shunt)

(CONT.)
ARDS
• Pathogenesis
• Common findings
• Decrease in lung compliance
• Due to loss or inactivation of surfactant with subsequent
increased recoil pressure
• Proteinaceous fluid fills alveoli and impairs ventilation

(CONT.)
ARDS
• Pathogenesis
• Common findings
• Decrease in FRC
• Very stiff, noncompliant lungs associated with alveolar
edema and exudate exaggerate surface tension forces
• Alveolar closure leads to atelectasis and loss of lung
volume
• Diffuse, fluffy alveolar infiltrates
• Noncardiogenic pulmonary edema

(CONT.)
ARDS
• Early
• Sudden marked respiratory distress
• Slight increase in pulse rate
• Dyspnea
• Low PaO2
• Shallow, rapid breathing

(CONT.)
ARDS
• Late
• Tachycardia
• Tachypnea
• Hypotension
• Marked restlessness
• Crackles, rhonchi on auscultation
• Use of accessory muscles
• Intercostal and sternal retractions
• Cyanosis

(CONT.)
ARDS
• Diagnosis
• Hallmark is hypoxemia refractory to increased levels
of supplemental O2
• ABG
• Hypoxia
• Acidosis
• Hypercapnia

(CONT.)
ARDS
• Diagnosis
• PFTs
• Decrease in FVR
• Decreased lung volumes
• Decreased lung compliance
• VA/Q mismatch with large right-to-left shift

(CONT.)
ARDS
• Diagnosis
• Chest x-ray
• Normal with progression to diffuse “whiteout”
• Open-lung biopsy shows
• Atelectasis
• Hyaline membranes
• Cellular debris
• Interstitial and alveolar edema

(CONT.)
ARDS
• Treatment
• Mostly supportive
• Enhance tissue oxygenation until inflammation resolves
• Identify underlying cause
• Address cause (ex: sepsis)
• Maintain fluid and electrolyte balance
• Increased fluid administration can produce or intensify
pulmonary edema
• Block system inflammatory cells

(CONT.)
ARDS
• Treatment
• Adequate oxygenation
• Volume ventilator using pressure support
• Mechanical ventilation with positive end-expiratory
pressure (PEEP)
• Increases FRV and prevents alveolar collapse at end-
expiration
• Forces edema out of alveoli

(CONT.)
ARDS
• Treatment
• Adequate oxygenation
• Supplemental O2
• >60% contributes to ARDS related to absorption atelectasis
• FIO2 reduced as soon as possible
• High-frequency jet ventilation (HFJV)
• Inverse ratio ventilation (IRV)
• Inhaled nitric oxide

(CONT.)
Infant Respiratory Distress Syndrome
(IRDS)
• Etiology
• Hyaline membrane disease
• Similar to ARDS
• Syndrome of premature neonates
• 60% infants born <30 weeks not treated with
corticosteroids
• 35% for infants receiving antenatal steroids
• 5% infants <34 weeks

(CONT.)
IRDS
• Etiology
• High risk factors
• Birth prior to 25 weeks gestation
• Birth at advanced gestational age
• Poorly controlled diabetes in mother
• Deliveries after antepartum hemorrhage

(CONT.)
IRDS
• Etiology
• High-risk factors
• Cesarean section without antecedent labor
• Perinatal asphyxia
• Second twin
• Previous infant with RDS
• Rh factor incompatibility

(CONT.)
IRDS
• Causes
• Primary cause is lack of surfactant
• Premature neonate has difficulty maintaining high
pressures needed for adequate oxygenation
• Related to soft, compliant chest that’s drawn inward with
each inspiratory contraction of diaphragm

(CONT.)
IRDS
• Pathogenesis
• The neonate with IRDS must generate high
intrathoracic pressures (25-30 mm Hg) to maintain
patent alveoli
• Leads to increased alveolar surface tension and
decreased lung compliance

(CONT.)
IRDS
• Pathogenesis
• Increased work of breathing and decreased
ventilation
• Progressive atelectasis
• Increased pulmonary vascular resistance
• Profound hypoxemia
• Acidosis

(CONT.)
IRDS
• Pathogenesis
• Secondary cause is immaturity of capillary blood
supply
• Leads to VA/Q mismatch, adding to hypoxemia and
metabolic acidosis
• Right-to-left shunt from open foramen ovale or patent
ductus arteriosus may increase hypoxemia

(CONT.)
IRDS
• Pathogenesis
• Progressive damage to basement membrane and
respiratory epithelial cells
• Causes patchy areas of atelectasis
• Increased capillary permeability and leakage of
high-protein fluid into alveoli
• Related to cellular damage, excess fluid administration,
high levels of FIO2

(CONT.)
IRDS
• Early
• Shallow respirations, diminished breath sounds
• Intercostal, subcostal, or sternal retractions
• Flaring of nares
• Hypotension, bradycardia
• Peripheral edema
• Low body temperature
• Oliguria
• Tachypnea (60-120 breaths/min)

(CONT.)
IRDS
• Late
• Frothy sputum
• Central cyanosis
• Expiratory grunting sound
• Paradoxical respirations (seesaw movement of chest
wall)

(CONT.)
IRDS
• Diagnosis
• ABG
• Hypoxemia, metabolic acidosis
• Hypercapnia and respiratory acidosis with progression
of disease
• Chest x-ray
• Diffuse whiteout or ground glass indicative of diffuse
bilateral atelectasis and alveolar edema
• Generalized lung hypoinflation

(CONT.)
IRDS
• Diagnosis
• Lecithin-sphingomyelin (L/S) ratio and desaturated
phosphatidylcholine concentration in amniotic fluid
• Determines ability of fetus to secrete surfactant
• > 2:1 incidence of RDS <5%
• Presence of phosphatidylglycerol = pulmonary maturity
• L/S ratio improves with administration of glucocorticoids
before delivery

(CONT.)
IRDS
• Treatment
• Prevention is primary goal
• Maintain adequate oxygen levels (50-90 mm Hg)
• Low FIO2 settings related to high levels over time may
result in further alveolar damage, primary persistent
pulmonary hypertension, and retrolental fibroplasia
• Mechanical ventilation with PEEP or continuous
positive-airway pressure

(CONT.)
IRDS
• Treatment
• Exogenous surfactant administration (bovine,
porcine, or synthetic)
• Decreases mortality 50%
• High-frequency ventilation
• Provides more uniform lung inflation
• Improves lung mechanics
• Improves gas exchange

(CONT.)
IRDS
• Treatment
• Antibiotics (infection after culture done or
prophylactically until blood cultures return)
• Supportive therapy
• Adequate intravenous nutrition
• Fluid and electrolyte balance
• Minimal handling
• Neutral thermal environment

PLEURAL SPACE DISORDERS
Pneumothorax
• Etiology
• Accumulation of air in the pleural space
• Primary pneumothorax
• Spontaneous
• Occurs in tall, thin men 20-40 years
• No underlying disease factors
• Cigarette smoking increases risk

(CONT.)
Pneumothorax
• Etiology
• Secondary pneumothorax
• 20,000 new cases annually
• Result of complications from preexisting pulmonary
disease
• Asthma, emphysema, cystic fibrosis, infectious disease
(pneumonia, TB)

(CONT.)
Pneumothorax
• Etiology
• Catamenial pneumothorax
• Associated with menstruation
• Primarily in right hemothorax
• Associated with endometriosis
• Tension pneumothorax
• Traumatic origin
• Results from penetrating or nonpenetrating injury

(CONT.)
Pneumothorax
• Pathogenesis
• Primary
• Rupture of small subpleural blebs in apices
• Air enter pleural space, lung collapses, and rib cage
springs out
• Secondary
• Result of complications from complications from an
underlying lung problem
• May be due to rupture of cyst of bleb

(CONT.)
Pneumothorax
• Pathogenesis
• Tension
• Results form buildup of air under pressure in pleural
space
• Air enters pleural space but cannot escape during
expiration
• Lung on ipsilateral (same) side collapses and forces
mediastinum toward contralateral side
• Decreases venous return and cardiac output

(CONT.)
Pneumothorax
• Pathogenesis
• Open “sucking” chest wall wound
• Air enters during inspiration but cannot escape during
expiration
• Leads to shift of mediastinum

(CONT.)

(CONT.)
Pneumothorax
• Small pneumothoraces (<20%) are usually not
detectable on physical exam
• Tachycardia
• Decreased or absent breath sounds on affected
side
• Hyperresonance
• Sudden chest pain on affected side (90%)
• Dyspnea (80%)

(CONT.)
Pneumothorax
• Tension and large spontaneous pneumothorax are
emergency situations
• Severe tachycardia
• Hypotension
• Tracheal shift to contralateral side
• Neck vein distention
• Hyperresonance
• Subcutaneous emphysema

(CONT.)
Pneumothorax
• Diagnosis
• ABG
• Decreased PaO2, acute respiratory alkalosis
• Chest x-ray
• Expiratory films show better demarcation of pleural line
than inspiratory
• Decompression of hemidiaphragm on side of
pneumothorax
• Pleural line with absence of vessel markings peripheral
to this line

(CONT.)
Pneumothorax
• Diagnosis
• ECG
• Axis deviations
• Nonspecific ST-segment changes
• T-wave inversions

(CONT.)
Pneumothorax
• Treatment
• Management depends on severity of problem and
cause of air leak
• Lung collapse <15%
• Patient may or may not be hospitalized
• Treat symptomatically and monitor closely
• Lung collapse >15%-25%
• Chest tube placement with H2O seal and suction

(CONT.)
Pneumothorax
• Treatment
• Chemical pleurodesis
• Promotes adhesion of visceral pleura to parietal pleura
to prevent further ruptures
• Thoracotomy
• Patients with further development of spontaneous
pneumothorax and blebs
• Surgery permits stapling or laser pleurodesis of ruptured
blebs

(CONT.)
Pleural Effusion
• Etiology
• Pathologic collection of fluid or pus in pleural cavity
as result of another disease process
• Normally, 5-15 ml of serous fluid is contained in
pleural space
• Constant movement of pleural fluid from parietal
pleural capillaries to pleural space
• Reabsorbed into parietal lymphatics

(CONT.)
Pleural Effusion
• Five major types
• Transudates
• Low in protein (ratio <0.5)
• Low in lactate dehydrogenase (ratio >0.6)
• Specific gravity <1.016
• Associated with severe heart failure or other
edematous states
• Cirrhosis with ascites, nephrotic syndrome, myxedema

Pleural Effusion
• Exudates
• High in protein (>0.5 mg/dl)
• High in LDH (>0.6)
• Causes
• Malignancies, infections, pulmonary embolism,
sarcoidosis, post-myocardial infarction syndrome,
pancreatic disease
Pleural Space Disorders (Cont.)Pleural Space Disorders (Cont.)

Pleural Effusion
• Empyema due to infection in the pleural space
• High-protein exudative effusion
• Results from infection in pleural space
• Hemothorax
• Presence of blood in pleural space
• Result of chest trauma
• Contains blood and pleural flood
• Hct of fluid >50% of Hct of peripheral blood

Pleural Effusion
• Chylothorax or lymphatic
• Exudative process that develops from trauma
• Results from leakage of chyle (lymph fluid) from thoracic
duct
• Rheumatoid pleural effusion
• Tuberculous pleuritis

Pleural Effusion
• Causes
• Changes associated with various types r/t changes
in pleural capillary hydrostatic pressure, colloid
oncotic pressure, or intrapleural pressure
• Imbalance in pressure associated with fluid
formation exceeding fluid removal

Pleural Effusion
• Pathogenesis
• Transudates
• Increased hydrostatic or decreased oncotic pressure
• Exudates
• Increased production of fluid r/t increased permeability
of pleural membrane
• Impaired lymphatic drainage

Pleural Effusion
• Vary depending on cause and size of effusion
• May be asymptomatic with <300 ml of fluid in
pleural cavity
• Dyspnea
• Decreased chest wall movement
• Pleuritic pain (sharp, worsens with inspiration)
• Dry cough

Pleural Effusion
• Absence of breath sounds
• Dullness to percussion
• Decreased tactile fremitus over affected area
• Contralateral tracheal shift (massive effusion)

Pleural Effusion
• Diagnosis
• Chest x-ray
• Pleural-based densities
• Infiltrates
• Signs of CHF
• Hilar adenopathy
• Loculation of fluid

Pleural Effusion
• Diagnosis
• Thoracentesis
• Analyze fluid and reduce amount of fluid
• pH, LDH, glucose
• Presence of pathologic bacteria
• CT or ultrasonographic tests
• Assist in complicated effusions
• Distinguish mass from large effusion

Pleural Effusion
• Treatment
• Directed at underlying cause and relief of symptoms
• Tension and spontaneous pneumothorax are
medical emergencies requiring treatment to
remove pleural air and re-expand lung
• Closed chest tube drainage (adults)
• Controversial in pediatrics

Pleural Effusion
• Treatment
• Thoracentesis
• Ultrasound useful for thoracentesis guidance
• Thoracotomy
• Control bleeding (>200 ml/hr)

NEUROMUSCULAR DISORDERS
Poliomyelitis
• Viral disease in which poliovirus attacks motor
nerve cells of spinal cord and brainstem
• 8 cases/year in United States
• All related to polio vaccine
• New cases rare related to mass vaccination
and usually occur in unvaccinated
immigrants
• 95% infections asymptomatic

(CONT.)
Poliomyelitis
• Symptoms
• Fever
• Headache
• Vomiting
• Diarrhea
• Constipation
• Sore throat
• Chronic respiratory insufficiency r/t previous disease
• Function generally recovers

(CONT.)
Amyotrophic Lateral Sclerosis
• Males > females (2:1)
• Prevalence 5:100,000
• Degenerative disease of nervous system
• Involves upper and lower motor neurons
• Progressive muscle weakness and wasting
• Muscles innervated from spinal and cranial nerves
affected
• Eventually profound weakness of respiratory muscles
and death

(CONT.)
Muscular Dystrophies (Duchenne)
• Etiology
• Hereditary (X-linked recessive)
• Occurs 1/3500 births
• Symptoms
• Progressive muscular weakness
• Initially in lower extremities, and wasting

(CONT.)
Muscular Dystrophies (Duchenne)
• Symptoms
• Respiratory muscles become involved
• Later years (20-30s)
• Leads to hypoxia, hypercapnia, frequent respiratory
infections

(CONT.)
Guillain-Barré Syndrome (Acute
Polyneuritis)
• Etiology
• Mortality about 3%
• Demyelination of peripheral nerves
• History of recent viral or bacterial illness (66% of
cases) followed by ascending paralysis
• Infection involving Campylobacter jejuni often
precedes diagnosis

(CONT.)
Guillain-Barré Syndrome
• Weakness and paralysis begin symmetrically in LEs
and ascend proximally to UEs and trunk
• Severe cases
• Respiratory muscle weakness accompanies limb and
trunk symptoms
• Natural history of disease leads to recovery
• Minor residual motor deficits (15%-20%)

(CONT.)
Myasthenia Gravis
• Etiology
• 2-5 cases/year/million persons in U.S.
• Primary abnormality at neuromuscular junction
• Impairment by decreased number of receptors on
muscle
• Weakness and fatigue of voluntary muscles
• Those innervated by cranial nerves
• Peripheral and respiratory muscles can be affected

(CONT.)
Myasthenia Gravis
• Symptoms often managed by appropriate
therapy
• Respiratory failure can be due to increasing
severity of illness or medication
• Individual episodes of respiratory failure are
potentially reversible

(CONT.)

CHEST WALL DEFORMITIES
Kyphoscoliosis
• Etiology
• Neuromuscular
• Muscular dystrophy
• Marfan syndrome
• Neurofibromatosis
• Friedreich ataxia
• Poliomyelitis

(CONT.)
Kyphoscoliosis
• Etiology
• Idiopathic
• Found in adolescents >11 years
• Female (7:1)
• Congenital
• Pott disease

(CONT.)
Kyphoscoliosis
• Pathogenesis
• Bone deformity of chest wall resulting from kyphosis
and scoliosis
• Higher deformity in vertebral column, greater
compromise of respiratory status
• Lung volumes compressed
• Atelectasis, VA/Q mismatch, hypoxemia

(CONT.)

(CONT.)
Kyphoscoliosis
• Dyspnea on exertion
• Rapid, shallow breathing
• Chest wall deformity
• Ribs protruding backward, flaring on convex side,
crowded on concave side
• Hypoxia , CO2 retention (late)

(CONT.)
Kyphoscoliosis
• Diagnosis
• Screening for scoliosis and kyphoscoliosis in school-
aged children is an excellent method
• PFTs
• Hypercapnia, hypoxia
• Decreased lung volumes and capacities
• Increased pulmonary arterial pressures
• Chest x-ray
• Accentuated bony curves

(CONT.)
Kyphoscoliosis
• Treatment
• Depends on severity and age of patient
• Curvatures <20 degrees
• Monitor on regular basis
• Postural exercise program
• External braces for moderate scoliosis

(CONT.)
Kyphoscoliosis
• Treatment
• Curvatures >40 degrees
• Electrical stimulation of paraspinal muscles
• Spinal fusion
• Spinal instrumentation (Harrington rod) placement for
surgical stabilization
• Curvatures >60 degrees
• Correlate with poor pulmonary function in later life

(CONT.)
Ankylosing Spondylitis
• Etiology
• More common in males (10:1)
• Common in 2nd or 3rd decade of life
• Cause is unknown
• 90% have positive HLA-B27 antigen
• Transient acute arthritis of peripheral joints (50%)

(CONT.)
• Etiology
• Chronic inflammation at site of ligamentous Insertion
into spine or sacroiliac joints
• Respiratory system affected by limited chest
expansion and formation of pulmonary fibrosis in
upper lobes

(CONT.)
• Pathogenesis
• Progressive, inflammatory disease
• Immobility of vertebral joints and fixation of ribs
• Inflammation affects articular processes, costovertebral
joints, sacroiliac joints
• Fibrotic response leads to joint calcification, ligament
ossification, and skeletal immobility

(CONT.)
• Low to mid-back pain and stiffness increased with
prolonged rest
• Pain and stiffness decrease with exercise
• Restrictive lung dysfunction
• Rib cage movement reduction
• Chest wall muscular atrophy
• Breathing by excursion of diaphragm with rib cage
immobilization

(CONT.)
• Diagnosis
• PFTs
• Decreased VC, TLC, compliance of respiratory system
(chest wall)
• Chest x-ray
• Changes are seen in sacroiliac joints
• Destruction of cartilage
• Erosion of bone
• Calcification
• Bony bridging of joint margins

(CONT.)
• Diagnosis
• Laboratory
• Elevated sedimentation rate (85%)
• Decreased RBC
• Increased WBC
• HLA-B27 antigen (90%)

(CONT.)
• Treatment
• Development of exercise program
• Breathing and mobility exercises
• Medications
• NSAIDs

(CONT.)
Flail Chest
• Etiology
• Results from multiple rib fractures r/t trauma to chest
wall
• Ribs fractured at two distant sites
• Results in unstable, free-floating chest wall segment
• Moves paradoxically inward on inspiration
• Sternal fractures can cause flail segment

(CONT.)
Flail Chest
• Pathogenesis
• Fracture leads to impairment of negative
intrapleural pressure generation
• Causes decreased lung expansion on inspiration
• Lung parenchymal injury
• Pulmonary contusion
• Decreased lung compliance
• Respiratory failure
• Interstitial and alveolar hemorrhage
• VA/Q abnormalities

(CONT.)
Flail Chest
• Paradoxical motion of chest wall
• SOB, cyanosis
• Pain on inspiration
• Hypotension
• Hypoxemia, low arterial PO2
• Pneumothorax, hemothorax, subcutaneous
emphysema are common

(CONT.)
Flail Chest
• Diagnosis and treatment
• ABG
• Managed with mechanical ventilation
• Causes entire chest to move as unit rather than
paradoxically
• Pain management

(CONT.)
Disorders of Obesity
• Etiology
• Excessive body fat
• BMI >30 kg/m2 based on body weight and height
• Men (19.9%); women (25.1%)
• Blacks > whites
• BMI >30 kg/m2 have increased mortality of 50%-100%
of those with BMI between 20 and 25 kg/m2

(CONT.)
• Pathogenesis
• Several hormones act on brain receptor to regulate
appetite and metabolism
• Leptin binds to brain receptors, causes releases of
neuropeptides
• Increase metabolic rate
• Ghrelin stimulates appetite

(CONT.)
• Pathogenesis
• May be associated with hypoventilation and airway
obstruction
• Pickwickian syndrome
• Increased abdominal size forces thoracic contents upward
into chest cavity
• Decreases lung expansion and diaphragmatic shortening
• Sleep apnea syndrome
• Soft tissue deposits in neck and tissue predispose person
to upper airway obstruction

(CONT.)
• Decreased alveolar ventilation, severe hypoxemia
• Somnolence (daytime)
• Shortness of breath
• Polycythemia
• Cor pulmonale
• Impotence
• Headache
• Enuresis

(CONT.)
• Diagnosis
• Self-evident on exam
• Laboratory
• Increased RBC
• Identify comorbid factors
• Hypothyroidism, Cushing syndrome, insulinoma,
diabetes, hyperlipidemia

(CONT.)
• Diagnosis
• ABG
• Hypoxemia, hypercapnia
• PFT
• Decreased chest wall compliance, VC, TLC, ERV

(CONT.)
• Treatment
• O2 (morbid obesity)
• Weight loss program
• Caloric intake promotes energy deficit of 500-1000
kcal/day
• Aerobic exercise
• Surgical intervention
• Gastric bypass

INFECTION OR
INFLAMMATION
OF THE LUNG
Pneumonia
• Inflammatory reaction in the alveoli and
interstitium caused by an infectious agent
• Causes
• Aspiration of oropharyngeal secretions composed
of normal bacterial flora or gastric contents (25%-
35%)
• Present as lung abscess, necrotizing pneumonia,
empyema
• Bacteroides, fusobacterium

Pneumonia
• Causes
• Inhalation of contaminants
• Virus
• Mycoplasma
• Contamination from the systemic circulation
Infection or Inflammation of theInfection or Inflammation of the
Lung (Cont.)Lung (Cont.)

Pneumonia
• Classifications
• Community acquired
• Hospital acquired
• Bacterial
• Gram positive
• Staphylococcus
• Streptococcus

Pneumonia
• Classifications
• Bacterial
• Gram negative
• Haemophilus influenzae
• Klebsiella
• Pseudomonas aeruginosa
• Serratia marcescens, Escherichia coli, Proteus spp

Pneumonia
• Classifications
• Viral
• Legionella
• Lives in H2O
• Transmitted by portable H2O, condensers, cooling towers
• Fever, diarrhea, abdominal pain, liver and kidney failure,
pulmonary infiltrates
• Treatment: macrolide antibiotic

Pneumonia
• Classifications
• Viral
• Mycoplasma pneumoniae
• Common in summer and fall
• Young adults
• Pneumocystis jiroveci
• Common in patients with cancer or HIV

Pneumonia
• Causes
• Fungal
• Aspergillus
• Released from walls of old buildings under reconstruction

Pneumonia
• Pathogenesis
• Acquired when normal pulmonary defense
mechanisms are compromised
• Organism enters lung, multiply, and trigger
pulmonary inflammation
• Inflammatory cells invade alveolar septa

Pneumonia
• Pathogenesis
• Alveolar air spaces fill with exudative fluid
• Consolidates and difficult to expectorate
• Viral pneumonia doesn’t produce exudative fluids

Pneumonia
• Severity of disease and patient age cause variation
in symptoms
• Crackles (rales) and bronchial breath sounds over
affected lung tissue
• Chills
• Fever
• Cough, purulent sputum

Pneumonia
• Viral
• Upper respiratory prodrome
• Fever, cough, hoarseness, coryza accompanied by
wheezing/rales
• Mycoplasma
• Fever
• Cough
• Headache
• Malaise

Pneumonia
• Diagnosis
• Chest x-ray
• Parenchymal infiltrates (white shadows) in involved area
• Sputum C&S
• Sputum from deep in lungs
• Laboratory
• WBC >15,000 (acute bacterial)

Pneumonia
• Treatment
• Antibiotic therapy
• Based on sensitivity of culture

Severe Acute Respiratory Syndrome
(SARS)
• Etiology
• Coronavirus associated with coronavirus (SARS-CoV)
• Primary mode of transmission through person to
person
• Respiratory droplets
• Contact with contaminated objects/surfaces touching
mouth, nose, eyes

SARS
• Pathogenesis
• Virus epidemic associated with milder disease in
infants/children
• Severe respiratory forms in adults
• Median incubation period 4-6 days
• Patients become ill within 10 days of exposure
• Overall mortality rate 10%
• 50% > 60 years of age

SARS
• Fever (>100.4)
• Myalgias
• Headache
• Nonproductive cough
• Dyspnea

SARS
• Diagnosis
• Chest x-ray
• Evidence within 1 week of symptom onset
• Laboratory
• Lymphopenia
• Normal/low WBC
• Elevated liver enzymes
• Prolonged activated PTT
• Presence of SARS virus

SARS
• Diagnosis
• Respiratory specimens
• Nasopharynx
• Oropharynx
• Sputum
• Stool specimens

SARS
• Treatment
• No definitive treatment recommendations
• Symptoms of pneumonia
• Hospitalization
• O2 therapy
• Mechanical ventilation
• Isolation
• Discontinued only after consultation with local public
health authorities

Pulmonary Tuberculosis
• Etiology
• Estimated 10 million infected in United States
• Multidrug-resistant TB
• 15% of cases
• Mortality 70%-90%
• Median survival of 4-16 weeks

• Etiology
• High-risk individuals
• Prior infection (90%)
• Malnourishment, immunosuppression
• Living in overcrowded condition
• Incarcerated persons
• Immigrants
• Elderly

• Etiology
• Causes
• Infection
• Inhalation of small droplets containing bacteria
• Droplets expelled with cough, sneeze, or talking
• Mycobacterium tuberculosis
• Acid-fast aerobic bacillus
• Infects lungs and lymph nodes

• Etiology
• Causes
• Involvement of distant organ systems
• Hematogenous spread during primary or reactivation
phase
• Disseminated disease
• Miliary tuberculosis causes hematogenous dissemination of
organisms

• Etiology
• Classifications
• Primary (usually clinically/radiographically silent)
• May lie dormant for years or decades
• Reactivating
• May occur many years after primary infection
• Impaired immune system causes reactivation

• Pathogenesis
• Entry of mycobacteria into lung tissue
• Alveolar macrophages ingest and process
microorganisms
• Microorganisms destroyed or persist and multiply
• Lymphatic and hematogenous dissemination
• T-cells and macrophages surround organisms in
granulomas
• Impairs immune system

• Pathogenesis
• Reactivation occurs if immunosuppressed
• Pathologic manifestation is Ghon tubercle or
complex
• Parenchymal complex
• Well-circumscribed necrotic nodule that becomes fibrotic
and calcified
• Lymph components

• History of contact with infected person
• Low-grade fever
• Cough
• Night sweats
• Fatigue
• Weight loss
• Malaise
• Anorexia

• Physical examination
• Apical crackles (rales)
• Bronchial breath sounds over region of
consolidation
• Malnourished

• Diagnosis
• Sputum culture (definitive diagnosis)
• Three consecutive, morning specimens
• Identify slow-growing acid-fast bacillus
• Take 1-3 weeks for determination
• DNA or RNA amplification techniques (diagnosis)

• Diagnosis
• Chest x-ray
• Nodules with infiltrates in apex and posterior segments
• TB skin test
• Doesn’t distinguish between current disease or past
infection

• Treatment
• Administer multiple drugs (antibiotics) to which
organism is susceptible
• Therapy is for 9-12 months for active disease
• Therapy shorter in persons exposed with no active
disease
• Add at least 2 agents to drug regimen when
treatment failure is suspected

• Treatment
• Providing safest, most effective therapy for shortest
period of time
• Ensuring adherence to therapy by using directly
observed therapy
• Nonadherence to therapy is major cause of treatment
failure

PathoPhysiology Chapter 23

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PathoPhysiology Chapter 23